问题
解答题
用递等式计算. ①2450-450÷18×25 ②
③
④
|
答案
①2450-450÷18×25,
=2450-25×25,
=2450-625,
=1825;
②
×2 5
+1 2
÷9 10
,9 20
=
+1 5
×9 10
,20 9
=
+2,1 5
=2
;1 5
③
+(5 16
-7 16
)÷1 4
,1 2
=
+(5 16
-7 16
)×2,4 16
=
+5 16
×2,3 16
=
+5 16
,6 16
=
;11 16
④
÷[(1 15
+2 3
)×1 5
],1 26
=
÷[(1 15
+10 15
)×3 15
],1 26
=
÷(1 15
×13 15
),1 26
=
÷1 15
,1 30
=
×30,1 15
=2.